I'd agree that this is likely a duplicate of bug https://bugs.launchpad.net/ubuntu/+source/gnome-panel/+bug/574247
It was certainly a hardware problem for me, swapping the Matrox out for an ATI cured it. Though I'd like to use the old Matrox as it drives my old good quality CRT monitors very well.
I'd agree that this is likely a duplicate of bug https:/ /bugs.launchpad .net/ubuntu/ +source/ gnome-panel/ +bug/574247
It was certainly a hardware problem for me, swapping the Matrox out for an ATI cured it. Though I'd like to use the old Matrox as it drives my old good quality CRT monitors very well.